Calling device for automatic telephone-exchanges.



A. E. KEITH & J. & 0.1. ERICKSON. CALLING DEVICE FOR AUTOMATIC TELEPHONEEXCHANGES.

APPLICATION FlLED MAY4, 1903.

Patented Aug. 24, 1915.

5 SHEETSSHEET 1.

.INVEN QMO L W 'E/ MI By MI WITNESSES: WW

A. E.- KEITH & J. & C. J. ERICKSON. CALLING DEVICE FOR AUTOMATICTELEPHONE EXCHANGES.

APPLICATION FILED MAY 4, 1903.

Pateiited Aug. 24, 1915.

5 SHEETS-SHEET 2-.

lNV'ENTORS A. E. KEITH & J. & 0;]. ERICKSON. CALLING'DEVICE FORAUTOMATIC TELEPHONE EXCHANGES.

APPLICATION FILED MAY 4,'l903.

Patented Aug. 24, 1915.

5 SH EE TSSHEET 3 AVE. KEITH & .l. & C. J. ERICKSON. CALLING DEVICEFOR'AUTOMATIC TELEPHONE EXCHRNGES. fkPPLldATION man MAY 4. 1903.

1,151,51. Patented Aug'. 24, 1915.

5 SHEETS-SHEET 4.

A. E. KEITH & 1. 6i 0. J. ERICKSON.

CALLING DEVICE FOR AUTOMATIC TELEPHONE EXCHANGES.

APPLICATION FILED MAY 4, 1903.

Patented Aug. 24, 1915.

5 SHEETS-SHEET 5 I ALEXANDER E. KEITH,

SOIL-OF CHICAGO, ILLINQIS, ASSIGN OBS, BY MES-NE ASSIGNMENTS, TO FIRSTTBU$T AND SAVINGS BANK, TRUSTEE, OI CHICAGO, ILLINOIS. v

CALLING DEVICE non auroiua'nc rnLnrnonn-nxcmens.

aianaai.

To all whom it may concern: 1-

Be it known that we, ALEXANDER E. KEITH, Jomv ERroKsoN, and] CHARLES J.Enrcnson, ALEXANDER E. Knrrn residingat Hinsdale, in the county ofDupage and State of Illinois, and JOHN ERICKSON and CHARLES J. 'Emcnsonboth residing at Chicago, in the county of Cook and tate of Illinois,have invented a new and useful Calling Device for AutomaticTelephone-Exchanges, of which the following is a specification.

Our invention relates to means at a subscribers station for controllingthrough a plurality of line wires electrical impulses through themagnets which operate switching devices comprising either a simple orantomatic telephone or telegraph exchange or central station, and ourobject is to provide for this purpose a more erfect construction than inthe invention em odied in our patent of theUnited States, dated January11 1898, number 597 ,062, in which we employ as, in the presentinvention, a step by step circuit breaker and a circuit changer, wherebya person at one station may intermittently and alternately energize aplurality of electro-magnets, one at a time, at the central station, theinitial movements of the operator being transmitted to the device bymeans of a series of movable finger holds, which may be arranged in manydifferent forms and adapted to be interconnected with the callin deviceswitching mechanism in many di ferent ways, but in this instance aredisposed in circular order, concentric with a shaft, which latter isadapted to revolve by the action of a finger engaged with someone of theholds, and operating against the resiliency of a spring, the latterbeing wound up a different amount for the movement of each finger-hold,and when any particular fingerhold has been moved up'to a stop and thenreleased the tension of the spring causes the parts to return to thenormal position, at a moderate rate of speed by virtue of a simplegoverning mechanism, causing theswitching devices in this returnmovement to serve as mediums through which an intermittent current ofelectricity is permitted to pass through a particular one of a pluralityof wires, each oonnected to a motor-magnet to be energized at thecentral station.

The particular improvements embodied in s emaanon of Letters Patent.Application filed May 4, 1903. Serial No. 155,582.

'two of which, g

each has a plurallty of terminals or contact "Patented Aug. 24:, 1915,

the present invention over the invention set forth in the herein'beforenamed patent consist'of a better construction of the circuit changer anda better means for producing the required number and duration of inter-,

mittent currents over any one or all of a plurality of circuits as maybenecessary for the duty of operating a simple or automatic telephoneexchange.

St1llanother improvement consists in means for locking the means throughwhich the mechanism is manipulated by virtue of the telephone receiver,until after the latter is removed, 'to prevent any one from carelesslyinterfering with the regular cycle of successive movements and therebypreventing the central exchange mechanism from elng the normal or firstposition ready for another call.

The mechanism by which these results are attained comprises a pluralityof circuits, in this instance five, the calling, local battery, ringing,receiver and release circuits,

points, part of which terminals are adapted to be closed successively,as by an intermittent circuit closer or wheel provided with teeth orcontact makers in making a call, other terminals are adapted to beclosed alternately as by a circuit changer for causing a current to bepassed over the calling circuit alternately to operate the switchingmechanism at the central exchange, other terminals are adapted to beclosed simultaneously to release the switching mechanism at the end of acall, as by the descent of the receiver hook when the receiver is hungup, and the other terminals are adapted to be closed insuch order ormanner as will be necessary to complete Said mechathe circuits in makinga'call. nism is described hereinafter and illustrated in theaccompanying drawings, in which- Figures 1, 2, 3 and 4 show,respectively, a front elevation; a plan; a rear elevation; and a sideelevation looking in the direction indicated by arrow A, Fig. 1, of theframe and operative mechanism. Fig. 5, is a transverse vertical sectionon broken line B, C, Fig. 2, looking in the direction indicated by arerow D, Fig. 6 is a transverse vertical section on broken line F, G, Fig.2, looking in partially operated and not released to the calling and therelease or nmsnann, AND JOHN Enrcixsou Ann CHAR-LES'J. Enron,

- receiver hook lever for closing the by the descent of this lever.

trated in Figs. 1, 3, 5 and 6. Fig. 14, also ing evices. Fig. 10 is aperspective view of a group of three switch springs, as they appear whenremoved from the other mechanism, to

plainly illustrate the relative position 'of a projection on one springwhich is adapted to be contacted by a projection on the telephonesprings randthe electric circuit therethrough. Fig. 11,.is a sideelevation of the springs shown in Fig. 10, together with the inneroendportion of the telephone receiver hook lever in the position when thesprings are closed F1 12, is the same as Fig. 11, but with the te e honereceiver hook in a different position rom that shown in Fig. 11, toillustrate the action of the upward movement of the telephone receiverhook lever, without closing the switch springs. Fig. 13, is an edgeelevation of a part which is attached to the telephone hook lever,as'plainly shown in Fig. 11, and is provided with two laterallyprojecting arms for operating the switch s ring mechanism shown inFigs.7, 8 and 9, and for closing the switch spring shown in Figs. 11 and12. Fig. 14 is an elevation of a part of the rear of the frame with aportion of the inner end of the telephone hook lever pivotally attachedthereto, and in a raised position, when a series of switch springsdifferent from those above referred to are in the closed position, onaccount of being out of contact with a projection from the telephonehook lever, which opens the spring when in the lowest or normal positionillusillustrates, in a small broken circular line, the position of astop pin on one of the rotative parts against a spring, which places oneof. the switch springs of the group shown in electrical connection withthe frame of the device, whenever the fingerhold disk and the impulseswitch wheel are in normal positions shown in Figs; 1 and 6.

Fig. 15 is diagrammatic, to illustrate the operationof the callingdevice when placed in electrical connection with an automatic telephoneexchange switch at a central ex-.

change, and is fully described hereinafter.

, Similar numerals indicate like parts throughout .the several views.The mechanism shown in the drawing herewith is all inclosed in asuitable protective case, not. shown, with the exce tion of thefinger-hold disk or actuator 2, ger

stop 3, and a portion of the front end of shaft 4, Fig. 2. Disk 2 isfirmly mounted on and insulated from the outer end of shaft 4, whichlatter is disposed through the central portion of the device, andrevolubly mounted in the frontand back plates 5 and 6 of the main frame.At the rear of disk v2 is a volu'te spring 7 having one end attached toshaft 4, and the other end to the main frame. Shaft 4 and disk 2 areheld in the normal position Fig. 1, against the resiliency of spring 7by an arm 8, F igs.

3, 7, 8 and 9, attached to the rear end of portion of shaft 4, which armcontacts a pin projecting from the main frame and -,forms, in thisposition, an electrical connection therewith.

Loosely mounted on shaft 4 is a wheel 10 which is provided with fineteeth, so, as to serve as airatchet wheel,and as a cog' wheel adapted toengage a small pinion 11 on shaft 12 upon which latter is mounted at theopposite end from pinion 11 a centrifugal speed governor 13, forregulating, by a variable frictional contact with a concentricstationary boss, the speed of revolution of not only wheel 10, to whichit is directly geared through pinion 11 integral with shaft 12, but therelease or, return'movement to the initial position of finger-hold disk2, the attached shaft 4 thereof, and all the depending parts hereinafterdescribed, for the purpose of preventing the desired intermittentelectric currents, for operating the magnets of the central exchangeswitches, being transmitted too rapidly, for

well known reasons.

In Fig. 5 is shown the wheel 10 and a portion 13 of the governingmechanism, and it also shows the inner end portion of the telephonehook-lever 14, which is pivotally attached to the main frame at 15.

At 16, Fig. 5, and not sgiown in Figs. 2 and 4, is a bent rod pivo allyattached to the short end of lever 14, the other end of the rod being inengagement with the end of a spring 17 which is attached to the lowerend of the main frame, and serves to lift the telephone receiver hooklever 14 to the second position, as in Figs. 8 and 9, after the removalof the receiver.

A pawl 18, Figs. 2, 3 and 6, is pivotally attached to lever 14 at 19,Fig. 5, and is adapted to engage the teeth of wheel 10.

Stop 20, Figs. 2 and 4, projects from the inside of the front frameplate 5, and serves to limit the downward movement of lever 14 under theweight of the telephone receiver, against the resiliency 'of spring 17.

Figs. 2, 4, 5 and 6 plainly show a make .and break terminal or contactas a spring contact a pendant terminal 22 which is attached to andinsulated from thejframe plate 6.

Firmly secured to shaft. 4:,is a segment wheel 23, Fig. 4, provided witha series of eleven actuators, I as teeth or projections which formcontact makers and number one more than the number of finger holds 24 indisk 2 and pivotally attached to wheel 23 is a pawl 25 which engages cogwheel 10.

There is a projection 26, Figs. 5 and 6, from make and break spring arm21 which is disposed at a slight angle in unison with a lateral bend inthearm, andis adapted to engage the teeth of segment wheel 23, so

as to cause the outer end of the arm to successively and intermittentlycontact the pendant terminal 22 as many times as there are teeth in thewheel 23, when the latter is moving in onedirection of revolution, buton account of the bevel on the teeth of wheel 23, and the angulardisposition of the projection 26 relative to the wheel, the arm is,heldfrom contacting the terminal 22 when the wheel is moving in theopposite direction.

At 27 is a spring having one end inlight contact with spring arm 21, toprevent undue lateral vibration of the latter.

A pin 28, Figs. 6 and 14, projects from segment wheel 23 which is inelectrical connection with the frame of the device. Pin

28 is normally in contact with a spring 29,

Figs. 1, 5, 6 and 14 and the latter is in electrical connection with amember 30 of a spring compound switch consisting of terminals or contactpoints as springs 30, 31,

32, 33 and 34.

Springs 33 and 34 are for the local battery circuit for the transmitter.Spring 32 and the projection 58 from telephone hook lever which isconnected with the frame are in the ringing circuit. Springs 29 to 30and 30 to 31 are in the receiver circuit. Since these springs are incircuits not particularly essential to illustrate this invention, exceptto show the relation of part of their terminals or contact points to thetelephone receiver hook andto the intermittent circuit closer of thecalling circuit, no further description is necessary.

In Figs. 3, 7, 8 and 9, is shown anarm 35 having one end pivotallymounted on the .rear frame plate 6, and serves not only as a lock toprevent the finger-hold disk from.

versation ended, the movements of the sev-- eral parts to attain thisresult being as follows: The normal position of the stop arm 8 isagainst pin 9, Figs. 3, 7 and 8, when the arm 35 is in the positionshown in Figs. 3 and 7, with the lower end thereof in the path indicatedby the circular broken line of a projecting pin 36.0r stop arm 8, whichosition prevents any upward movement o the latter 'or of the connectedfinger-hold disk. If, now, the telephone receiver 37 is removed from thehook, and the lever 14 rises by, virtue ofspring 17, a projection 38 onthe lever contacts arm 35, and the latter is lifted to the fpositionshown in Fig; 8, above the path 0 the pin 36 on stop arm 8, in whichposition arm 35 still holds switch sprin or.

terminal 39'but of contact with the terminal 40, which'latter is inelectrical connection with the pendant terminal 22, but should thefinger ho indicated by arrow E, Fig. 1, which causes the stop arm 8'tom'ove as indicated by arrow F,Fig. 8, the pin 36 on stop arm 8 servesto lift arm 35 to the, position shown in Fig. 9, when switch spring 39,being released, falls into contact with 40, and through it is placed inelectrical connection with terminal 22.

The calling device circuit changer comprises a disk 41, mounted ininsulating mated disk be moved in the direction rial on the rear end ofshaft 4. One half of disk 41 is of smaller diameter than the other, andtherefore out of reach of two insulated springs or terminals 42 and 43which are so disposed that the free end of but one spring at a time isin contact with the disk. A. spring 44 secured to the main frame ininsulating material, Figs. 3 and 4, is in contact with disk 41 andserves to always electrically connect the disk through wire 45,

Fig. 15, with make and break spring arm 21.

In this manner the disk has two contact points, one of which is the flatsurface with which the spring or terminal 44 of one of the circuitscontacts at all times, and the other one is the periphery of the largerportion and is movable into and out of engagement with either of theterminals 42 and 43 of the other circuit, said terminals 42 and 43 beingpreferably diametrically oppositeto each other and in such position asto engage only with the periphery or larger portion of the disk.

In the 'dia rammatic view, Fig. 15, is shown the ca ing device, andanautomatic telephone exchange switch connected by line wires 46' and 47line wire 46 being bifurcated and connected at one end to switch springsor terminals 42 and 48 at the callmg device, and at. the other end, atthe central ,exchan e is normallyl in electrical connection with t ebattery t rough circuit chan er switch-arm 49, wire 50, vertical magnet5, and battery wire 59. The other line wire 47 is bifurcated andconnected at the calling device with switch springs or terminals 43 and52 and the end at'the central exchangg with an auxiliary switch magnet71, wire Switch spring 39 at the calling device is insulated from thepart to which it is attached, but is brought into contact therewith whenthe calling device is in electrical connection from ground through wire57 and the pendant terminal 22 which is attached to part 56, and whichwe hereinafter referto.

There are a number of switch springs 30, 31, 32, 33 and 34 shown inFigs. 1, 5, 6 and 14, which are connected with the talking and ringingcircuit, not shown, but thesesprings arefor the purpose of opening thiscircuit by the gravity of the telephone receiver, when on the hook, asshown in Figs.

1, 5 and 6, where a projection 58 from the telephone hook lever 14contacts and moves spring 32, which, through the pads of insulatingmaterial between springs 32 and 33 and 30 and 32 causes springs 33 and34 and 30 and 31 to separate. After the telephone is removed from thehook, the above named springsassume the position shown in Fig. 14, withthe circuitclosed.

Switch springs 48, 52 and 54 form triple terminals which serve tocontrol the electric current for releasing the switch mechanism at thecentral exchange, so that it may return to the initial position readyfor another call, and these springs are shown in the open position inFigs. 3, 10, 12 and 15.

The action of the telephone lever in closing the release circuit isshown in Figs. 12 and 13.

In Figs. 4 and 10 is plainly shown a lateral projection 48 from theinner spring 48 which is in the path of'a projection from the telephonelever 14.

When the telephone lever is rising after the removal of the telephone,projection 60 engages the projection 48 on the concave side shown inFig. 10 and moves it away from the adjacent spring 52, as shown in Fig.12, but when the lever is descending the projection 60 contacts theopposite or convex side of the spring projection 48 and moves the springfirst, into contact with center spring 52, when these springs areconnected, respectively, with line wires 46 and 47 then, by this contactand further-downward movement of projection 60 center sprin 52 isbrought into contact with outer spring 54, as shown in Fig. 11, whenboth springs 48 and 54 are in connection through wire 55 with terminal22, Fig. 15, the insulated part or bracket 56 and the terminal 40thereof, and with the ground wire 57, ifspring 39 is in contact with theterminal 40, as shown in Fig. 9.

The triple switch springs or .terminals 48, 52 and 54 are inthe centralexchange switch release circuit, and the manner in which these springsare operated by the descent of,

operated. The helical spring 67 holds de- .end of which is attached anarm 69. The

spring 63 normally holds the armature 62 in the position shown. 1 ,64 isa detent shaft upon which are secured two detents 65 and 66, which,respectively engage with the teeth of the vertical ratchet 73 and therotary ratchet 74, on switch shaft 79 when the instrument is being tents65 and 66 in yielding engagement with t the ratchets.

A pin 68 projects from detent shaft 64 and is disposed in the path ofmovement of .a

bent lever catch-pawl 69, which latter is yieldingly held in position byspring 70. At 7 5 is the vertical magnet whose armature is attached tolever 7 6 to which is pivoted a pawl for engaging vertical ratchet 3 inoperatlng shaft 79 step by step vertically. Lever 7 6projects to Withina short distance of detent shaft 64, so that, when this lever isoperated by the vertical magnet 75, the outer end of the lever isadapted to strike the inwardly projecting end of release pawl 69,- andremove the latter from "engagement with the detent shaft pin '68 andpermitthe detents 65 and 66 to be move by virtue of helical spring 67,into enga ement, respectively, with vertical ratchet 3 and rotaryratchet 74 at the proper time. When the detent shaft 64 is operated soas to lift detents 65 and 66 from engagement with ratchets 73 and 74 arod 84, having one end pivotally attached to detent 66 and the othertipped with'insulation, contacts with and moves the switch lever 49 fromconnection with wire'83 to connection with wire 50 or into its normalcondition.

' In operation, if it is desired to set a subscribers telephone switchat the central exchange to communicate, for instance, withtelephone'switch and telephone number 35, first remove the telephonereceiver from the hook when arm 35, at the calling device will be movedfrom the osition shown in Fig. 7 to that shown in Fig. 8, when arm 8,shaft 4, and the finger-hold disk 2 are free to move. Referring to Fig.1, the operator now laces a finger in contact with fin erhold l lo. 3,which is pulled down aroun in r the direction indicated by arrow,E,until the finger contacts the sto 3 and is withdrawn, when finger-holdisk 2 is released and by virtue of spiral spring 7 carried 1:0

backwardly, together with shaft 4, and connected selgment-wheel 23- tothe normal 120- 11 thus manipulating the fingerarm 35 from the positionshown in Fig. 8,.

when contact spring 39 falls into electrical connection with .arm 40 ofthe insulated part 56 which is in electrical connectionwith pendantterminal 22, Figs. 1, 2 and 4. Also in the first movement downwardly,the insulated circuit changer has been moved ,from the position shown inFig. 3 to the position shown in Fig. 9, or the segmental roken lines inFig. 15-, out of contact with switch spring 43 and into contact withswitch spring 42. In the second or back- .ward movement, on account ofsegment wheel 23 having one more beveledvtooth of the whole number thanin the whole number of finger-holds on plate 2, and this extra toothbeing placed angularly ahead, relativel to the arran ement of thefingerholds, t e segment W eel teeth operating spring, arm 21, causesthe latter. to separately contact endant terminal 22, four times instead0 three, when the first three of these impulses pass from battery 77wires 59 and 78, vertical ma net 75 wire switch arm 49 line wire 46 t ento the calling device, spring 42, disk 41, spring 44, wire 45,

spring arm 21, terminal 22, part 56, arm 40 then spring 39, wire 57 toground, and b electro-magnet 75 operate main switch sha t 79 threeupward steps. But just before the last electrical impulse of the fourabove described, the circuit changer. disk 41 has been moved from theposition in contact with s ring 42v to contact with sprin 43, when thislast impulse asses from attery 77 through wire 59, wire 72, auxiliaryelectromagnet 71 and line wire 47, spring 43, disk 41, spring 44, wire45, spring arm 21, pendant terminal 22, part 56, arm 40, spring 39 andwire 57 to ground, causing the auxiliary electro-magnet 71, vto operatethe switch arm 49 so that line wire 46 is moved out of connection withwire 50 and into connection with wire 83, which leads to the rotaryelectro-ma et 51. This far main switch shaft 79 has been lifted threesteps,

and communication established with the rotary magnet, which before wascut out of circuit. If now, the finger-hold disk is moved from the fifthhold to the stop, and six impulses sent over the line wires, five ofthese impulses would pass from battery 77 through wire 53,electro-magnet 51, wire 83, then the moved switch arm 49, wire 46 spring42, disk 41, spring 44, wire 45,

spring arm 21, pendant'arm 22, part 56, arm

40, spring 39 and wire 57 to ground and thereby causing rotary magnet 51to revolve shaft 79 five steps. When the disk 41 "changes theeircuitfrom line wire 46 to 47 the efiect is to. simply operate the armature ofauxlliary magnet 71, which would have no efiect upon' switch lever 49'since it would be in the second position in communlcation with wire 83.k

In the manner described the switch shaft 79 would have a wiper armin'electrical con- IlGCtlOIl'Wltll contact point No. 35 of somesubscribers line not shown.

In the operation of release, a subscriber hangs the telephone on thehook when arm 14 escendmg in the manner hereinbefore described, causesthe switch spring 52 and 48 to first contact, and thus connect linewires 46 and 47, then they are grounded simultaneously by being broughtinto contact with spring 54, which causes a simultaneous current. overboth main lines 46 and 47 with the result, that the auxiliary magnet isoperated to close springs 80 and 81, when current passes through releasemagnet 61, closing its armature 62 and permitting'the hook arm '69,attached thereto, to engage with the pin 68, which projects from detentshaft 64, and when the circuit is broken by the additional descent oftelephone lever 14, the strong spring 63 controlling lever armature 62lifts the latter and withdraws the pawis 65 and 66 to the position shownclear of ratchets 73 and 74, and moves the rod 84 so as to return theswitch lever to its normal position, when the main switch shaft 7 9.11sfree to return to the initial position by virtue of gravity and thespring 82 at the lower end portion. We claim as our invention:

' 1. A device of the character described comprising a plurality ofcircuits, an intermittent circuit closer adapted to be included ineither of saidcircuits, a circuit controller, means for operating thecloser and controller alternately, and means for closing said circuitssimultaneously.

2. A device of the character described comprising two circuits, anintermittent circuit closer adapted to be included ineithcr circuit andthe other one is adapted to loee a release circuit, a telephone receiversupport movably mounted and having connection with said othercircuit-closing means to hold said circuit open: until said receiver ortis moved'in one direction, substanasset forth; 7

5. A'device of the character described comprising a plurality ofcircuits, an intermittent circuit-closer and a circuit-changer.

connected to move in unison, the circuitchanger having a single contactsurface circuit-chan r, substantially as set forth.

- contact makers, a finger hold piece for operthe action of the '6. In ate ephone exchange callin device, a plurality of circuits, the callingan releas- 1 ingcircuits of which each has a plurality of terminals, anintermittentcircuit closer, a circuit changer-having two contact points,one of which is common to said calling circuits and the other point ismovable into and out of engagement with either of two of the terminalsof said two circuits, and means for operating the changer during theoperation of the circuit closer.

7. In a telephone exchange calling device, a plurality of circuits, twoof which are each provided with a pluralit of terminals, a

circuit closer provided with a plurality of contact makers, a circuitchanger having two contact points, one of which is common to both ofsaid two. circuits and the other one is movable into and out ofengagement with two of the terminals of said two circuits before theclosing of one ,of the circuits by the action of the last contact maker.

8. In a telephone exchange calling device, a plurality of circuits, twoof which are each provided with a luralit of terminals, a circuit closerprovided with a plurality of ating the same and having one less holdthan there are contact makers, a circuit changer having two contactpoints, one of whichis common to said two circuits and the other one ismovable into and out of contact with two of the terminals of said twocircuits, and means for movin said changer before the closing of one oft e circuits by ast contact maker.

9. In a tele hone exchange calling device, a lurality o circuits, acircuit closer provi ed with inclined teeth, a flexible memberprojecting into the path of said teeth, a finger hold piece foroperating the closer, and a circuit changer for changing the circuitsbefore the last tooth engages said member.

10. In a telephone exchange calling device, a plurality of circuits, twoof which are each provided with a plurality of terminals, anintermittent circuit closer and a circuit changer, said changer beingprovided with two contact points, one of which is flat and common toboth of said two circuits and v the other is curved and movable into andout of engagement two said two circuits'.,; 1

11. In a telephone exchange calling de of the terminals of vice, apluralit of circuits, an intermittent circuit closer, t ree terminals,one of which is common to two of said circuits, and a substantiallycircular, disk-like circuit changer, the periphery ofwhich is oftwodiameters, one face of the disk being in constant contactlwith one ofsaid three termi-w nals and the portion of the periphery havin thelarger diameter being movable into an out of engagement with either oneof the other terminals. i 1 12. In a telephone" exchange callingdevice,a plurality of circuits, two contact closers, one of which is adaptaedto alternately close said circuits "intermittentI when making a call,and the other one 15 adapted to closeboth circuits simultaneously so Iwhen the call is completed, a receiver hook,

and means for operating said closers, the means forclosing the circuitssimultaneously being controlled by the receiver hook.

13. In a telephone'exchange callin device, a rotary intermittent circuitc oser;. adapted to rotate forward and back, a lock for holding the sameagainst movement,'and" a movable telephone receiver hookprovided withmeans for releasing said circuit closer as the hook is being raised. 7

14. In a telephone exchange calling device, a rotary intermittentcircuit closer adapted to rotate forward and back, a lock for holdingthe same against movement, and a movable telephone receiver supportprovided with a shoulder for engaging with the lock and releasing it asthe support is being raise a 15. In a telephone exchange calling de-vvice, two circuits, each provided with'a plurality of movable terminals,an intermittent circuit closer for closing one of the circuitsintermittently through a part of the terminals, a lock' for controllingthe movement of one of said terminals and for locking the closer againstmovement, and means for releasing said lock. v

16. In a telephone exchange callingjdevice, two circuits, each providedwith a plurality of terminals, an intermittent circuit closer for one ofthe circuits, and means for locking the closeragainst movement and alsofor holding the terminals of the other circuit separated. v

17. In a telephone exchange calling device, two circuits, each providedwith a plurality of terminals, an intermittent circuit I closer for oneof the circuits, a lock for holding the terminals of the other circuitseparated, and a telephonereceiver support provided with means forreleasing said lock.

18. In a telephone exchange calling device, a plurality of circuits, twoof which each has a plurality of terminals, means for closihg part of,said terminals byjthe telephone receiver hook when it is moved in onedirection, and means for closing other of said terminals beforethe'first mentioned part of the terminals are separated when the hook ismoved in the opposite direction.

19. In a telephone exchange calling device, a plurality of circuits, twoof which each has a plurality of terminals, an intermittent circuitcloser for one of the circuits a receiver hook, means for locking saidcloser against movement, means for unlockv ing the circuit-closer whensaid hook is raised, means for closing part of the terminals of onecircuit an releasing the intermittent closer when the telephone receiverhook is moved in one direction, and means for closing a art of theterminals of the other circuit be ore the first mentioned part of theterminals are separated when the hook is moved in the oppositedirection.

20. In 'a telephone exchange calling device, a plurality of circuits,two of which each has a plurality of terminals, a receiver hook, meansfor closing part of the terminals of one of the circuits by thetelephone receiver book when it is moved in one direction, and means forsimultaneously closing part of the terminals of the other circuit beforesaid first mentioned art of the terminals are separated by the ookwhenit is moved in the opposite direction.

21. In a telephone exchange calling device, a plurality of circuits,part'of which each has a plurality of terminals, means for closing partof the terminals of one of said circuits when the telephone receiverhook reaches the limit of its upward movement,

means for closing other terminals when the hook reaches the limit of itsdownward movement, and means for closin still other of said terminalswhen the hook is at a point intermediate said limits on its downwardmovement. 1

. 22. In a telephone exchange calling device, a plurality of circuits, acircuit changer, and means for simultaneously closing the terminals oftwo of said circuits by the descent of the telephone receiver hook, oneof which terminals is adapted to control a releasing circuit.

23. In a telephone exchange calling de vice, a plurality of circuits, a.platefor controlling1 one of said circuits, a tele hone re= ceiver ookprovided with threes oulders, one of which is adapted to engage withsaid plate, and the other two control respectively direction butpreventing such engagement when the wheel moves in the oppositedirection, and means for electrically connecting the circuit changerwith the spring terminal so as to' pass a current over either one, oftwo circuits.

the terminals of other of said circults.

24. Ina telephone exchan e' calling device, a frame, a shaft journa edtherein, an actuator secured to one'end'o'ffthe shaft and a circuitchanger'to the-riothemnmeans for limiting the movement of the actuator,contacts for engaging with the changer, an intermittent circuitcloser-mounted on the menace venting the movement of the actuator untilafter the telephone receiver has been removed from its support. v

25. In a telephone exchange calling device, a frame, a shaft journaledtherein, an actuator and a circuit changer secured to but insulated fromthe respective ends' of the shaft, means for-limiting the movement ofthe actuator,-contacts for on aging with the changer, one of which is eectrically connected with the frame and two are ada ted shaft within theframe, and a lock for preto engage with the circuit changer a ter-" ofthe actuator, contacts for enga 'ng with thecircuit chan er, one of whrcis electrically connecte with the frame and two are adapted to engagewith the circuit changer alternately,'a flexible terminal secured to theframe atone end, an insulated terminal on the frame in position tobeengaged by the spring terminal, a toothed wheel on the" shaft inposition for en agin with said spring terminal intermittent y an forcingits free end into engagement with the insulated terminal, and means forelectrically connecting the circuit changer with said spring terminal soas to pass a current over either one of two circuits.

27.111 a telephone exchange calling device, a frame, a shaft journaledtherein, an actuator and a circuit changer secured to but insulated fromthe respective ends of the shaft, means for limiting the movement of theactuator, contacts for engaging with the circuit changer, one of whichis electrically connected with the frame and two are adapted to engagewith the circuit changer alternately, a flexible terminal secured to theframe at one end and provided with an inclined projection, an insulatedterminal on the frame 1n position to be engaged by the spring terminal,a wheel on the shaft provided with inclined teeth in position to engagewith said inclined projection and succcssively force the free end of thespring terminal into engagement with the insulated terminal when thewheel ismoved in one 28. In a telephone exchange calling deing anactuator and a circuit changer secured to but insulated from therespective ends of the shaft and an intermittent circuit closer securedto the intermediate portion, a spring for returning the shaft to itsnormal position, means for limiting the movement of the actuator, a lockfor preventing the movement of the actuator, and means 'for releasingthe lock by the movement of the telephone receiver hook-31f 29. In atelephone" exchange calling dei vice, a frame, a shaft jenrnaled thereinhaving an actuator and a circuit changer. se-

cured to but insulated from the respective ,15' ends of-the shaftand anintermittent circuit closer secured to' the intermediate portlon, aspring for returning the shaft to its normal position, means forlimiting the movement of the actuator, an arm for locking the actuatoragainst movement, and. means for moving thearm to release the actuatorby the movement of the telephone receiver hook 30. In a telephoneexchange calling device, a frame, a shaft journaled therein having anactuator and a circuit changer secured to but insulated from therespective ends of the shaft and an intermittent circuit closer securedto the intermediate portion, a

spring for returning the shaft to its normal position, means forlimiting the movement curedto but insulated from the respective ends ofthe shaft and an intermittent circuit closerv secured to theintermediate portion, a spring for returning the shaft to its normalposition, means forlimiting the movement of the actuator, a shoulderedarm-secured to "the shaft, a locking arm in position for engaging withsaid shoulder and locking the actuator against movement, and means formoving the lock out of engagement with the shouldered arm to release theactuator when the receiver is-removed from'its support.

-' 32. In a telephone exchange calling device, a' frame, a shaftjournaled therein having an actuator and a circuit changer secured tobut insulated from the respective ends of the shaft and an intermittentcircuit closer secured to the intermediate portion, a spring forreturning the shaft to its normal position, means for limiting themovement,

of the actuator, an insulated spring terminal,,a shouldered stop armsecured to the] shaft, a shouldered locking arm for engaging with theshoulder of the stop arm and locking the actuator against movement,'a

shouldered receiver hook for engaging with the frame, two of which areflexible and two of them are insulated, a contact maker on the shaftadapted to force the free end of the non-insulated terminal into contactwith the rigid insulated terminal, a lock for holding the actuatoragainst movement and also for holding the flexible insulated terminalout of contact with the frame, and means for moving said lock to releasethe actuator and to permit said insulated flexible terminal to contactwith the frame when the receiver hook is moved upward.

34. In a telephone exchange calling device, a releasing circuitincluding a group of three terminals, one of which is shouldered, and areceiver hook rovided with means for engaging with sai shoulder andforcing all three terminals into simultaneous engagement.

35. In a telephone exchange calling device, a group of three terminals,some of which are for the calling and releasing circuits, respectively,and some of which are for the talking and ringing circuits, and meansfor separating the talking and rin ing circuits when the receiver hookdescen s and permitting them to contact when it 36. In a telephoneexchange calling device, a frame provided with calling and releasemechanism, a plurality of terminals, three of which are insulatinglysecured together and 'two of said three are movable 1 into and out ofengagement with two other "of'said group and one of them is connectedwith the calling clrcuit, and a rejection on the receiver hook inposition or engaging with one of said three terminals and forcin saidtwo terminals out of contact with and permitting them to contact whenthe hook rises.

37. In a telephone exchange callingdevice, a frame, a shaft journaledtherein, an actuator and a circuit changer secured to but insulated fromthe respective ends of the shaft, and an intermittent contact closer onthe shaft within the frame, a governor mounted in the frame, one end ofthe shaft of which is provided with a pinion, a fine toothed wheeloosely mounted on the shaft in position for engaging with said pinion,a, pawl on the circmt closer for engaging e other two when the hookdescends I with said wheel on the return movement of the closer, and atele honereceiver hook provided with a paw for engaging with I -vice, aframe, a shaft journa ed thereiman actuator, a circuit changer and anintermittent circuit closer secured tothe shaft and a fine toothed wheelloosely mounted'on the shaft, a governor connected with said wheel, latelephone receiver hook pivotally secured to the frame, a springactuated rod and a pawl secured to the inner end of the hook,

and a pawl on the circuit closer for engag:

ing with said wheel on the return movement of the circuitcloser. I

39. In a telephone exchange calling de y .vice, a frame, a flexibleterminal secured at one end thereto, means for intermittingly movingsaid terminal, and a brake for preventin undue vibration of theterminal.

40. n a telephone exchange calling device, a frame, a flexible terminalsecured at one end thereto, means for intermitt'ingly movingsaidterminal, and'a sprin for enof the terminal and preventing undue viration thereof.

41. In combination, a calling device for electrical exchanges, linelimbs associated therewith, an impulse transmitter for sending currentsover said limbs, actuating means therefor, ahook lever normally causingsaid means to be locked, and apparatus automatically worked on removalof the receiver from the hook lever to perform a pre- 7 liminaryswitching operation and thereafter unlock said actuating means. g I 42.In a telephone system, a calling mechanism, said vmechanism providedwith a rotary calling dial ada ted to rotate forward and back providewith a curved and concentric line of holes, a numeral or indicatingdevice for each hole and means for variably limiting the forwardrotation of the dial'in accordance with the hole selected thereon.

43. In a telephone system, a'calling mechanism,-said mechanismcomprising a rotary dial adapted to rotate forward and back, governingmechanism for retarding the return of said dial to normal, and means forvarying the return movement of the dial.

a telephone system, a calling mechanism, a hook-switch associatedtherewith, means 0 erated by the downward movement of the ook-switch forreleasing the said mechanism, and a governor for retarding the downwardmovement of the hook-switch.

45. In a telephone system, a calling mechanism, a hook-switch associatedtherewith,

means 0 erated by the downward movement of the ook-switch for releasingthe said mechanism, and a overnor operative to retard the downwardmovement of the hookswitch and the return movement of the callingmechanism to normal. 46. 'In a telephone system, a rotary impulsetransmitter adapted torotate forward and back, a switch hook, and meansoper- I ated by one of said elementsto control the other.

47. In a calling device for telephoneexchanges, a rotary dial adaptedtorotate forward. and back, means for normally locking controlled by theswitch hook in its upward movement to release said wheel.

'49. In a telephone system, an impulse transmitting device including aground connection, a pair of normally open spring contacts forcontrolling said ground connection, a switch hook for normally lockingsaid transmitter against operation, means controlled-by the upwardmovement of said switch hookfor unlocking said transmitter, and meanscontrolled by the initial operation of said transmitter for closingsaid'contact springs and ground connection.

50. In atelephone system, an impulse transmitting device including arotary calling dial, a ground connection, a pair of normally opencontacts controlling said connection, a switch hook normally lockingsaid calling dial against rotation, means 0 erated by the upwardmovement of said switch hook for unlocking said dial, and meanscontrolled by the forward movement of said dial for closing said contactsprings and said ground connection.

51. In a telephone system, a line circuit, a calling device including arotary dial,'and means controlled by a single operation of said dial.for transmitting a plurality of impulses over one side of said linecircuit,

followed'by a single impulse over the opposite side thereof.

52. In a telephone system, a line circuit, a calling device including arotary dial, means for variably operating said dial, and meanscontrolled by one of said operations of said dial for transmitting'avarylng number of impulses, depending upon the extent of operation ofsaid dial, over one side of said line, followed by a single impulse overthe opposite side of saidline.

53. In a telephone system, a line circuit, a calling'device including arotary dial, and means controlled by each single operation of said dialfor transmitting a plurality of impulses over one side of said linecircuit, followed by a single impulse over the oppol 54. Inatelephonesystem, a line circuit, a calling device including a rotarydial, means for variably operating-salddial' in accordance with thedigits Ofa called nllmher, and means controlled by each one of saidopm'atlons of said dial for transmitting a varying number of impulses,"depending upon the extent of operation of said dial over one side ofsaid line, followed by a single impulse over the opposite side of saidline.

55. In a telephone system, a calling mech-- v anism, said mechanismprovided with a rotary calling dial adapted to rotate forward and backprovided with a curved and concentric line of finger holds, a numericalindicating device for each hold, means for variably limiting the forwardrotation of the dial in accordance with the hold selected, a rotarygoverning mechanism for retarding the return .of-the said dial to normaland automatic'means for connecting the governmg mechanism to the dialduring the geturn movement thereof and for disengagingthe dial from saidgoverning mechanism" upon the forward movement of the d1al,. saidcalllng mechanlsm comprlslngmeans whereby the governing mechanism isrotated a variable amount 1n accordance with the variable operations ofthe dial.

56. In a telephone system, a calling mechamsm, and means for sending 1mulses, said mechanism comprising a rotary dlal adapted to' rotateforward'and back, rotary governing mechanism for retarding the return ofsaid dial to normal,.means for varying the return movement of the dialand. automatic means for connecting the governing meeh anism to thedialdurin the return movement thereof and for disengaging the dial from saidgoverning mechanism upon the forward movement of the dial, said callingmechanism comprising means whereby the governing mechanism is rotated,a'variable amount in accordance with thevariable op erations ofthe dial.

57. In a telephone system, a calling mechanism, said mechanism providedwith a rotary dial adapted to' rotate forward and back, provided with acurved and concentric line of finger holds, rotary governing means forretarding the return of said dial to normal, means for varying thereturn movement of the dial in accordance with the holds selectedthereon and automatic means for connecting the governing mechanism tothe dial during the return movementthereof and for disengaging the dialfrom said governing mechanism "upon the forward movement of the dial,said calling mechanism comprising means whereby the governing mechanism1s rotated a variable amount in accordance with the variable operationsof the dial.

58. In a telephone system, a calling mechanism for sending impulses,said mechanism comprising a rotary dial and means whereby the dial 7 maybe variably rotated forward and back, a rotary governing mechanism forretarding the return of said dial to normal, and'means for curing thegoverning mechanism tothe d1al.-during the return move ment thereof,.and'for disengaging the dial from said gear upon the forward movementofthe dia.

59. In a telephone system, a calling mechanism provided with a callingdial and means'wherebythedial may be rotated for- J anism, means forsending impulses, said mechanism comprising a dial and means 1 wherebythe dial may be rotated forward and back, rotary go'verning 'mechanis'mfor retarding the return of said dial to normal, means for varying thereturn movement of during the return movement thereof and fordisengaging the dial from-said governing ,mechamsm upon the forwardmovement of the dial.

61'. In atelephone system, a calling mechanism provided with a:- dialand means whereby the dial may be rotated forward and back, said dialprovided with finger holds, rotary governing mechanism for retarding thereturn of said dial to normal,

the dial, and automatic means for-'connect- I ing the governingmechanism to the dial means for varying the return movement of V thedial in'accordance with the holds selected thereon, and automatic meansfor connecting the governing mechanism to the 'dlal during the returnmovement thereof and for disengaging the dial from said governingmechgniim upon the forward movement of the In testimony whereof we havesigned our 1 names to this specification in the two subscribingwitnesses.

ALEXANDER E. KEITH. JOHN ERICKSON. CHARLES J. ERICKSON.

Witnesses SAMUEL Com, Oscar SNELL.

presence of It is hereby certified that in Letters Patent No. 1,151,541,granted August 24, 1915, upon the application of Alexander E. Keith, 01Hinsdale, and John Erickson and Charles J. Erickson, of Chicago,Illinois, for an improvement in Calling Devices for AutomaticTelephone-Exchanges, errors appear in the printed specificationrequiring correction as follows: Page 1, line 91, for the word receiverread receiver;

page 5, line 97, after the word lever insert the reference-numeral 49;page-6,,

line 82, claim 12, for the word adaptaed read adapted; same page, line 127, claim 17, for the word lock read circuit-closer; and that the saidLetters Patent should be read with these corrections therein that thesame may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 7th day of December, A. D., 1915. I

' R. F. ITEHEAD.

[SEAL] Cl. 179--90. Acting Commissioner of Patents,

